<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="./hammer.min.js"></script>
</head>
<body>
    <div id="content">
        <button class="btn">btn</button>
    </div>

    <script>
        // hammer需要先初始化
        var h = new Hammer(document.getElementById('content'));
        h.on('tap', function() {
            console.log('hello');
        })
    </script>
</body>
</html>